Under the 1996 Safe Drinking Water Act (SDWA) Amendments, the U.S.
Environmental Protection Agency (USEPA) was mandated to propose a revised maximum
contaminant level (MCL) by January 2000 and promulgate a final Arsenic Rule by January
2001. The USEPA officially released the draft Arsenic Rule in June 2000 and promulgated
the final Arsenic Rule in January 2001. With the promulgation of this rule, the arsenic MCL
was revised downward to 10 ug/L. Among the most notable differences between the
proposed and final arsenic rules is the requirement that non-transient non-community
(NTNC) water systems will be required to comply with the proposed MCL, not simply
monitor for arsenic and notify those affected. This requirement will require an estimated
1,000 NTNC systems to remove arsenic from their water supplies. Most of
these systems are very small with limited resources thereby necessitating simple and cost
effective treatment solutions.
Based on a review of United States Geologic Survey data, Washington ranks approximately
17th in arsenic in groundwater sources, with other Western States such as California, Nevada,
Arizona, and Utah ranking much higher. Although arsenic is not as prevalent in the
groundwater of Washington as it is in many other states, it will arguably have a greater
impact on more systems in the state than any rule promulgated by the USEPA within the past
10 years. In addition, there have been cases where arsenic in private wells has exceeded
5,000 ug/L (Frost et al., 1993). As a result of these concerns, the Department of Health
(DOH) Division of Drinking Water convened a cross-disciplinary group of staff to assist
purveyors, counties, and other local health jurisdictions to understand and act upon the issues
related to arsenic in groundwater.
Fortunately, there is a wealth of information on arsenic treatment and associated issues to
assist in the development of treatment guidance that is readily understood by owners and
operators of very small systems. With all this information, the focus of treatment technology
assistance will be to assist purveyors in understanding the issues associated with appropriate
treatment technologies. The most appropriate technology for a given source will depend
upon a number of factors including:
system size;
arsenic concentration;
other water quality parameters (pH, Fe, Mn, etc . . .);
existing treatment; and,
residual disposal options.
Includes 8 references, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 610 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 6 |
| Published : | 11/01/2002 |
